Of course this stupendous head-dress gives the moose quite an imposing appearance; and it is one of the wonders of the naturalist what can be its object. The horns are found only on the males, and attain their full size only when these have reached their seventh year. In the yearlings appear two knobs, about an inch in length; in two-year-olds, these knobs have become spikes a foot high; in the third year they begin to palmate, and antlers rise along their edges; and so on, until the seventh year, when they become fully developed. They are annually caducous, however, as with the common deer, so that these immense appendages are the growth of a few weeks! The haunts and habits of the moose differ materially from those of other deer. He cannot browse upon level ground without kneeling or widening his legs to a great extent: this difficulty arises from the extreme length of his legs, and the shortness of his neck. He can do better upon the sides of steep hills, and he is often seen in such places grazing _upward_. Grass, however, is not his favourite food: he prefers the twigs and leaves of trees--such as birch, willow, and maple. There is one species of the last of which he is extremely fond; it is that known as striped maple (_Acer striatum_), or, in the language of hunters, "moose-wood." He peels off the bark from old trees of this sort, and feeds upon it, as well as upon several species of mosses with which the arctic regions abound. It will be seen that in these respects he resembles the giraffe: he may be regarded as the giraffe of the frigid zone. The moose loves the forest; he is rarely found in the open ground--on the prairie, never. On open level ground, he is easily overtaken by the hunter, as he makes but a poor run in such a situation. His feet are tender, and his wind short; besides, as we have already said, he cannot browse there without great inconvenience. He keeps in the thick forest and the impenetrable swamp, where he finds the food most to his liking. In summer, he takes to the water, wading into lakes and rivers, and frequently swimming across both. This habit renders him at that season an easy prey to his enemies, the Indian hunters, for in the water he is easily killed. Nevertheless, he loves to bury himself in the water, because along the shores of lakes and margins of rivers he finds the tall reed-grass, and the pond-lily--the latter a particular favourite with him. In this way, too, he rids himself of the biting gnats and stinging mosquitoes that swarm there; and also cools his blood, fevered by parasites, larvae, and the hot sun. The female moose produces one, two, and sometimes three calves at a birth; this is in April or May. The period of gestation is nine-months. During the summer, they are seen in families--that is, a bull, a cow, and two calves. Sometimes the group includes three or four cows; but this is rare.